Apparatus for grinding cutlery



6 Sheets-Sheet '1j.

(No Model.)

lA. JOHNSTON; APPARATUS. F013. GRIN DIN G GU'IVVLERY.

Patented Sept, 5,

` Q ...di

(No Moda.) 6 sheets-sheet 2.

A.. JOHNSTON.

APPARATUS FOR @BINDING GUTLBRY.

No. 504,387. 3 Patented Sept. 5, 18.93.

(NovModel.) 6 Sheets-Sheet 3.'

A. JOHNSTGN. APPARATUS'FOR GRINDING GUTLBRY. No; Y 504,387'.

Patented Sept. 5,

LIJIIIII I `lill-Ill] (.No Model.) 6 Sheets-.Sheet 4. A. JOHNSTON.

APPARATUS' POR GRINDING GUTLERY. No. 504,387, Patented Sept. 5, 1893.

(N Model.) 6 sheets-sheet 5.

AJOHNSTON. APPARATUS FOB. GRINDINGUUTLERY.

` No. 504,387. Patented sept. 5, 189s;

FIC- X-II".

l A6 Sheets-Sheet 6.

'Patgntedsepn 5,1893.

A. JOHNSTON'. APPARATUS Pon GRINDING GUTLERY.

(No Model.)

NITED STATE-s PATENT Ormes..

ALLEN JOHNSTON, OF OTTUMWA, IOWA.

APPARATUS For: GRINDING ouTLERY.

SPECIFICATION forming part of Letters Patent No. 504,387, datedSeptember 5, 1893. Appnoooioo moo ooooboo 1e, iseaf Soriana-149,249.`(No modoi.)

To all whom it may concern):

Beit known that I, ALLEN JOHNSTON, of Ottumwa, in the county ofA Wapelloand State of Iowa, have invented a new and useful lmprovementinApparatus for Grinding Cutlery, which is fully set forth in thefollowing specification. y

The present invention relates to the art of cutlerygrindin g, andparticularlyto the grinding of articles of various sorts upon which anirregular surface is to be produced by the grinding operation,necessitating an irregular feed, in contradistinction to operations thatmaybe termed regular, as grinding the flat surfaces of disks, caseknives, dac., or the curved surfaces of mandrels, spindles, izc.

The blades of pocket knives may be taken as an illustration of the'classof articles to which this invention has more particular reference. trueshape by grinding it must be ground flat on the side for a greater partof its length,

and then gradually rounded ed toward the point. The back is also to beground flat for the greater part of its length and then rounded towardthe point. When the blade is chamfered on one side, as usual with largeblades, there is a third operation involving an irregular feed.

One object of my invention is to effect the grinding of these, andsimilar irregular surfaces, by means of automatic feeding devices. Atpresent (unless the work is held and guided by hand) the sides of pocketknife blades are usually groundby being fed and held against a rotatinggrinder of greater thickness than the length of the blade. This simplygrinds a flat surface leaving the rounding of the blade toward the pointto be iinished by hand. It has, however, been proposed to employ anannular grinder, and to feed the knife blade across the same, thegrinding beginning at the point of the knife. f

Another operation in the fashioning of pocket knife' blades consists informing a shouldernear the end which is attachedto the handle. In themanner in which such blades, (and other articles having a similarshoulder) are ground, the shoulder cannot be properly cut by grinding,andv must be finished by hand, the reason being that the corner of thewheel which forms this shoulder To bring such aknife-blade toits iscontinually wearing away and becoming The invention includes mechanismwhereby the operation indicated above may be accomplished. The automaticfeeding and workv holding mechanism comprises a slide by which the workis carried and which is capable of moving in any direction in one plane,actuating mechanism for reciprocating the slide to grind the flatsurface, and a cam or former (whose shape will depend on the particularcontour to be given to the Work) for delecting the slide to grind theirregular or curved portion of its surface. In moving laterally towardand from the grinding surface the slide may swing on a center, or movebodily in guides. The specific motions of the slide are, of course,relative to the grinding wheel,and it is immaterial which of thesedevices is relatively movable. Special improvements included in thispart of the invention will be fully described hereinafter. o

The invention further comprises automatic means for adjusting the wheelwith reference to the work holder. The arbor of the grinding-wheel hasheretofore been made adjustable lengthwise by means of a hand Wheel.

According to the present invention the wheel is moved forwardintermittently by automaticdevices, the amount of motion beingsufficient to compensate for wear. Inasmuch as the amount of wear willvary with the hardness of the steel acted upon, aswell as with thecomposition of the wheel itself, the invention includes'means forregulating the amplitude of motion given to the Wheel at each automaticadjustment. The required amount of motion being ascertained and theadjusting mechanism regulated accordingly, the Workman has no ,furtherconcern with IOO the adjustment of the wheel. Preferably the mechanismis so constructed as to effect an adjustment at the end of each completemovement of the work holding slide, and it is also preferred to providethe machine with an automatic stop to arrest the feed mechanism at theend of each movement. This is desirable because one workman in practicesupervises several of these machines, and unless' very watchful he wouldnot always be ready to stop the machine and remove the work at theproper moment.

In order that the invention, and the best mode in which I nowcontemplate applying the principle thereof, may be fully understood, lwill explain the same more in detail, reference being had to theaccompanying drawings, which illustrate the construction of a machinehaving work-holding and feeding mechanism designed for grinding theblades of pocket knives.

Figure I, shows in side view a knife blade after grinding in accordancewith this invention. Fig. Il, is alongitudinalsection on line II andFig. III a transverse section on line III of Fig. I. Fig. IV,illustrates the present mode of grinding the shoulder on the blade. Fig.V, illustrates the improved mode of forming the shoulder wholly bygrinding. Fig. VI, is a horizontal section of a machine constructed inaccordance with the invention, the section being through the axis of thegrinder and the work holding devices being shown in plan. Fig. VII is afront elevation partly in vertical section. Fig. VIIIisa centralvertical longitudinal section, the grinding wheel and its arbor beingshown in side elevation. Fig. IX, is a vertical cross-section on line IX(Fig. VI) looking to the rear. Fig. X, is a partial plan view of thework holding devices arranged to grind the back of the knife. Figs. XIand XII are details in longitudinal vertical section and transversesection respectively of the work-holding slide and accessory parts. Fig.XIII is a detail of the oscillating segment for conveying motion to theslide. Fig. XIV, is a detail in plan of the automatic stop mechanism forarresting the feed slide at the end of its stroke. Figs. XV and XVI aredetails illustrating part of the automatic adjusting mechanism for thegrinding wheel.

Referring to Figs. I to V, a represents a knife blade ground to propershape. From the shoulder a', which should he nearly square, to thedotted line III the blade is flat, and from that line to the point a2 itis curved or tapered as shown in Fig. II. If ground straight to the endin the ordinary way the blade would have the same thickness at the pointa2 as at the other points along the section of Fig. II, and the curvedpart of the cutting edge would have to be formed by a separateoperation. The back a3 of the blade is ground flat from the right handend to the dotted line III, and from that line is rounded or curved tothe point a2.

The chamfered portion a4 presents the same features as the side of theblade, that is to say, it has a square shoulder and is dat to about thedotted line III, and then curved to the point a2.

In grinding the side of the blade, if the point is first brought incontact with the wheel, and then fed along until the rear end of thesurface to be ground reaches the wheel, (as is done in grinding tableknives, dac.) the eect will be as shown in Fig. IV, in which brepresents part of the grinding wheel. In that method the greater partof the wear occurs at the corner b of the wheel which acts first uponevery part of the blade, the wear on the grinding face increasing indegree toward this corner and gradually rounding it, as indicated in thedrawings. Consequently, except upon the first few articles ground, therequired shoulder cannot be cut by the wheel, rendering anotheroperation necessary.

rPhe improved method is illustrated in Fig. V. According to this planthe blade a. is first fed directly against the wheel extending acrossand beyond the grinding face as shown. The shoulder is thus cut by thesharp corner, and the blade then fed away from this corner (instead oftoward it) until the point of the blade is ground. In practicing thismethod it will be readily seen that the wear on the face of the wheeldiminishes toward the corner b', by which the shoulder is cut, it beingthe opposite corner b2, which sustains the maximum wear; and that theeffect of the abrasion of the wheel in this case is to keep the corner bsharp.

Referring now to the other drawings, the grinding wheel b is of the ringor cup form described in Letters Patent No. 377,201, granted to meJanuary 3l, 1888, and is mounted on a horizontal arbor B, suitablysupported in bearings, and provided with the usual fast and loosepulleys. The wheel turns in a trough B adapted to contain water and tosupply it by a spout B2 to the interior of the wheel, and the latter ispartly inclosed by a guard or casing B3, all substantially as inmachines described in previous patents. The work holding slide C restson a dovetailed support C (Figs. XI and XII) and can reciprocatethereon. This support has a tubular portion C2 IOO IIO

which is pivoted in a socket C3 in the frame (Fig. VII). Consequentlythe slide C, by the rotary movement of support O', and by its ownindependent reciprocating movement, is capable of universal motion in ahorizontal plane. It can therefore (when properly guided) he moved in,or parallel with the plane of rotation of the grinder, then toward thelatter to bring blade ct against it, to begin the operation of grindingat the shoulder (this being the position of the parts as shown in Fig.VI), then back `in a right line, grinding the dat portion ofthe blade,and then in a curved line, compounded of its own motion and the axialmotion of the supportC, grinding the curved portion of the blade.

The devices for reciprocating the workholding slide yare in somerespects such as have heretofore been used. The novel features of thispart of the construction reside mainly, in the automatic guiding of theslide in irregular lines, and in the means for starting and stopping thesame. Slide C has on its under side a rack c which engages a pinion c onthe end of an upright shaft c2, which has a similar pinion con its lowerend. Pinion c3 is engaged and actuated by a segmental arm D (Figs. VIIand XIII) which is pivoted at d to the frame and is oscillated by meansof a pin d attached to the arm D and entering a cam groove d2 in thedrum or cam Wheel D (see Fig. VIII). This gives the slide C areciprocating motion transversely to the axis of the grinder. Shaft c2is made in two parts for convenience in removing the slide and itssupport when desired. The upper part is fastened by a pin 10 to a ring11, and the lower part similarly fastened by a pin 12 to a ring 13. Thetwo rings are coupled by upright pins 14, 15, which are fast in one ofthe rings (thelower) and t loosely in holes in the upper. Thus the upperpart of the shaft may be readily uncoupled from the lower. This, of4course, is merely a convenient arrangement, and not an essential featureof the construction.

To grind the side of a blade as in Fig. VI, the slide C must have amotion towardthe wheel in the direction of the axis thereof. To this enda guide arm E is detachably secured by screws or otherwise to slide C.At.

its free end this arm has twopins or rollers e', e2, the latter beingcarried on the end of a spring E which presses it toward the roller e.Between these rollers or pins is a guideV bar or former F, whichcontrols the positionsy of the slide C axially as it is reciprocatedback and forth. It will be obvious from inspection of the drawings thatas the rollers e', e2 follow the guide bar F the slide C, while movinglengthwise, will be turned on the axis of shaft c2 as a center when thecontour of said bar deviates from a line parallel with the plane ofrotation of the grinder, and by giving to the guide-bar or former asuitable outline the work-holding slide may be turned in eitherdirection, and to any desired extent, within certain limits. i

Special importance is not attached to the particular devices describedfor guiding the work-holder, as these may obviously be modifled, orreplaced by other devices capable of performing substantially the samefunctions. The essential feature or principle of this part of theinvention consists in providing automatic means for giving thework-holder an irregular movement.

As shown in Fig. VI the guide, cam, or former F, is secured rigidly tothe long lever F pivoted to the frame at f and capable of horizontaloscillation. The ,function of this lever is to swing the work-holdertoward the wheel so that the corner b may strike the out, as alreadyexplained. This motion is communicated to lever F .in the following way;Said lever has on its under side a recess f which is entered by awrist-pin f2 on a disk F2. Disk F2 is carried by an upright spindle Gsuitably supported in bearings in the frame, and having at its lower endan arm G which extends horizontally toward the cam wheel D and has a ping which enters a second cam groove g in the periphery of said wheel(Figs. VII and VIII). Through these connections the lever F is at theproper moment turned in the proper direction to throw the knifeybladeinto contact with the wheel. The shape of the cam grooves d2 gwill, of course, depend upon the character of the work to be done. Asshown in Fig. X the lever F and its actuating mechanism are not alwaysessential. In that figure the grinding'of the back of the knife blade isillustrated. In

this instance the guide arm vE is provided Y with a single pin or rollere entering a cam groove e3 in a stationary guide plate E2. This grooveis straight for a certain distance and then curved, so that the slide Cwill vtravel in a line parallelwith the plane of the grinding surfaceuntil the curve in the back of the knife blade is reached, and then bedeflected so as to keep the curved part of the blade against the wheel.The cam groove here is the obvious equivalent of the cam bar in theother figures.

The means for starting and stopping the feed movement will next bedescribed. Power is transmitted from the shaft 16, having the loosepulley 17, and fast pulley 18, to the shaft 20, having band pulleys 21(Figs. VI and IX), the speed of the latter shaft being much less thanthat of the former. On the inner end ofshaft 2O is a small pinion 22(Figs. VI and VII) which engages and drives a large toothed wheel Hwhich is on the shaft H carrying the cam wheel D. Shaft H is thus drivenat a low rate of speed. The belt which drives shaft 16, from which thefeed-movement is derived, is controlled bya belt shipper K (Figs. VI andXIV) carried by a rod L, extending backward from thefront of theframe,and having at its forward end an elbow or bend L2 for maniagainst theframe, and tends to push the rod' backward, or in the direction to throwthe belt from the fast pulley 18 to the loose pnl-- ley 17.Consequently, whenever the rod is released it at once arrests the feedmovement. RodL may be moved in the opposite direc- -tion to start thefeed bymeans of a treadle N, rock-shaft N and upright arm N2 (Figs. VIIand VIII). The upper end of arm N2 lies between two bosses n n2 on acollar'nwhich isv screwed fast to rod L. Arm N2 is also springy andpresses against the collar 'rt which has a at surface onthe sideadjacent to said arm, g

as seen in Fig. VII. Rod L also carries a finger or detent m, screwedfast to the rod so IOO I'IO

IZO

as to follow it in either a longitudinal or an axial movement. When thebelt is on the loose pulley this detent or finger m bears with slightpressure on the rim H2 of wheel H, the pressure being due to theresiliency of arm N2 bearing as already explained against the collar fn,which at this time is tilted at a slight angle to said arm. To start thefeed, the operator puts his foot on treadleN swinging arm N2 forward,moving rod L lengthwise in the same direction, and shifting the belt tothe fast pulley. This movement of rod L carries linger m past the rim H2of wheel H, and the pressure of arm N2 on collar n turns the rod Lslightly until the flat face of said collar is parallel with the saidarm as shown in Fig. VII. This slight rotary movement of rod L is justsufficient to carry finger m inward so that its free end is caught andheld by the edge of rim H2. Consequently, though the operatorimmediately removes his foot from the treadle, rod L is retained in thisposition against the pressure of its spring M, and the work-feedcontinues in operation. Rim H2 is provided at one point with adepression or notch 72. (Figs. VII and VIII). When this notch comesopposite detent m, the latter is no longer held, and spring M at onceacts, pushing rod L back and shifting the belt to the loose pulley. Thisnotch is in such position that the feed is arrested at the moment whenwork-slide C reaches the end of its return movement (to the right inFig. VII). When now the operator inserts a new piece of work into theholder he puts his foot on the treadle and shaft H begins to rotate, camgroove cl2 begins to oscillate arm D and slide C moves toward the axisof the wheel bringing the work opposite the grinding face of the latter.Pin d now travels for a while in a straight part of groove d2, duringwhich time groove g swings arm G and lever F', as explained above,bringing the blade up against the wheel until the shoulder is cut. Whenthis movement is completed groove d2 swings arm D in the oppositedirection, and slide C begins to retreat keeping the blade in contactwith the grinder. The movement is at first in a right line, grindingaflat surface on the blade, but as the slide nears theV end of its travelit is deflected by the action of the guide-arm E and the curved part ofguide-bar or former F, thus moving in a line which is the resultant ofits rectilinear and rotary movements, grinding the curved part of theblade terminating at its point. At this moment the reciprocatingmovement of slide C ends, and cam groove g causes it to turn away fromthe wheel, and on the completion of this movement the releasing notch hcomes opposite detent m, and the feed is automatically arrested.

In case of any accident necessitating the stoppage of the feed before itcompletes its movement this can be effected by slightly depressing thebent end L of rod L, turning the latter far enough to release detent mfrom engagement with rim H2, and permitting spring M to shift the beltfrom the fast pulley.

The special construction and disposition of parts for effecting thestarting and stopping of the feed movement, while advantageous, admit ofmuch modification, the broad novel features of this part of theinvention residing in the starting of the feed movement by means of afoot treadle, and the automatic stoppage thereof at the completion ofeach movement.

The mechanism for automatically adjusting the grinding wheel atintervals to compensate for wear will now be described. The arbor B ofthe wheel is surrounded by a sleeve P having bearings in the frame inwhich it can move longitudinally without turning. Sleeve Pis screwthreaded externally (Fig. VI) for a portion of its length and engaged byan adjusting wheel Pwhose hub is threaded interiorly, and which is heldfrom endwise movement by two collars pp', which form the bearings ofsleeve P. WheelP' has a threaded rim which is engaged by a small pinionq (shown in dotted lines Figs. IX and XV) on a short shaft q which hasbearings in a bracket q2. This shaft also carries a ratchet wheel Q withwhich engages a pawl r, pivoted on a plate R which swings freely onshaft q. Pawl r is held in engagement with ratchet Q by a spring r'(Fig. XV). Plate R receives motion from an upright rod S which passesthrough a hole in boss R of said plate and is secured by a set screw S.The lower end of the rod S is jointed to an arm T projecting from a rockshaft T (Fig. IX). The forward end of this shaft carries a lug t whichlies in the path of a pin t projecting from the rear of Wheel H, (Figs.VIII and IX.) This pin makes contact with lug t once in each rotation ofwheel H, depressing it and giving an upward thrust to rod S, this motionbeing transmitted by the pawl r, ratchet Q and pinion q, to theadjusting Wheel P. The grinding-wheel is thus moved a short distancetoward the work holder. It is obviously desirable that this adjustmentshould be capable of regulation to meet varying conditions of work. Thismay be elfected by loosening the set screw S and moving the rod Sdownward to lengthen the stroke of the pawl r, or upward to shorten itsstroke.

Many departures maybe made from the details of construction hereindescribed and shown without departing from the spirit of the invention,and some of the elements of the machine may be replaced by devicesequivalent in function. For example, I may substitute for a shiftingbelt and fast and loose pulleys, other Well known means for starting andstopping a shaft.

Having now fully described my said invention, what I claim, and desireto secure by Letters Patent, is-

l. In a machine for grinding articles having an irregular surface, thecombination with a grinding wheel, of a work-holder capable of universalmotion in one plane, and an irregular guide for controlling themovements of said workholder, substantially as described.

2. In a machine for grinding articles having an irregular surface, thecombination with a grinding wheel, of a work-holding slide supported soas to be capable of universal motion in one plane, means forreciprocating said slide in line with the grinding surface of saidwheel, and a guide of irregular outline for deflecting said slide fromthe line of its reciprocating movement, substantially as described.

8. The combination with the grinding Wheel, of a work-holder, a swiveledsupport therefor, means for reciprocating said slide on its support, aguide for changing the positions of said support and slide while thelatter is reciprocating on the former, a movable support or levercarrying said guide, and means for moving said support or lever towardand from the grinding surface of said wheel, substantially as described.Y

, 4. The combination with the grinding-wheel, of a Work-holder, aswiveled support therefor, a pinion on a shaft concentric withV the axisof said support and engaging a rack on said work-holder, means foroscillating said shaft, and a guide controlling the movements of saidsupport on its axis, substantially as described.

5. In a grinding machine for grinding knife blades and other articleshaving a shoulder thereon, the combination with the grindingwheel, of awork-holder capable of` moving transversely to the grinding Asurface andalso parallel therewith, means for feeding said Work-holder toward thegrinding surface so as to present the article latwise against the wheeland rst grind the shoulder by the corner of the wheel, and means forsubsequently traversing the work-holder with the article in contact withsaid wheel, across the grinding face thereof and in the direction awayfrom the said corner, substantially as described.

6. In a grinding machine, the combination with the grinding Wheel, ofthe automatic feed-mechanism for moving the work to, against, and awayfrom the grinding wheel, a starting and stopping device such asabeltshipper, a spring tending constantly to actuate said device in thedirection to arrest the feed, a detent for holding said spring duringthel feed-movement, and means for automatically releasing said springand putting the stopping device into operation at the completion of thefeed movement when the work is away from the Wheel, substantially asdescribed.

v 7. In a grinding machine, the combination with the wheel, of thefeed-slide, driving mechanism for moving said slide toward andfrom thewheel, a spring-actuated rod for disconnecting thegsaid drivingmechanism and arresting the feed, a treadle or lever for withdrawingsaid rod against the pressure of said spring and thus starting the feed,a catch or detent engaging and holding said rod when retracted by saidlever or treadle, and means for releasing said catch or detent at theend of the movement of the feed-slide, substantially as described.

8. lThe combination with the grinding Wheel and automatic feedmechanism, of a starting and stopping device such as a belt-shipper, anactuating rod therefor, a treadle for shifting said rod in the directionto start the feed, a detent for holding the rod in this position, andmeans for releasing the detent automatically at a predetermined moment,substantially as described.

9. In a grinding machine, the combination with Work-holding devices, ofa rotary grinder, an adjusting wheel for moving the grinder in thedirection of the work-holder, and means for intermittently actuatingsaid wheel, substantially as described.

10. The combination with the work holding devices, of a rotary grinder,a wheel for adj usting said grinder with respect to said Workholdingdevices, and gearing connected with a moving part ofthe machine foractuating said adjusting wheel intermittently, substantially asdescribed. 1l. In a grinding machine, the combination with thework-holder and its actuating devices, of a rotary grinder,intermittently operating mechanism for moving said grinder toward saidwork-holder to compensate for wear, and means for regulating the amountof such motion at each adjustment, substantially as described.

In testimony whereof I have signed this specification in the presence oftwo subscribing witnesses.

ALLEN JOHNSTON.'

Witnesses:

J. T. HAcKwoRTH, A. G. HARROW.

ICO

